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Environmental monitoring and fuzzy synthetic evaluation of municipal solid waste transfer stations in Beijing in 2001-2006 被引量:7
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作者 LI, Chunping LI, Guoxue +2 位作者 LUO, Yiming LI, Yanfu HUANG, Jian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第8期998-1005,共8页
Transfer station(TS)is an integral part of present-day municipal solid waste(MSW)management systems.To provide information for the incorporation of waste facilities within the current integrated waste management syste... Transfer station(TS)is an integral part of present-day municipal solid waste(MSW)management systems.To provide information for the incorporation of waste facilities within the current integrated waste management system,the authors measured the existing environmental quality at five MSW TSs.Discharged wastewater,air,and noise were monitored and assayed at the five TSs in Beijing in 2001-2006 during rainy seasons(RSs)and dry seasons(DSs).Except Ammonia(NH_3)and hydrogen sulfide(H_2S),the analytical results... 展开更多
关键词 municipal solid waste(MSW) transfer stations(TSs) pollutant monitoring environmental quality fuzzy mathematics
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Study on resource quantity of surface water based on phase space reconstruction and neural network 被引量:5
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作者 曹连海 郝仕龙 陈南祥 《Journal of Coal Science & Engineering(China)》 2006年第1期39-42,共4页
Proposed a new method to disclose the complicated non-linearity structure of the water-resource system, introducing chaos theory into the hydrology and water resources field, and combined with the chaos theory and art... Proposed a new method to disclose the complicated non-linearity structure of the water-resource system, introducing chaos theory into the hydrology and water resources field, and combined with the chaos theory and artificial neural networks. Training data construction and networks structure were determined by the phase space reconstruction, and establishing nonlinear relationship of phase points with neural networks, the forecasting model of the resource quantity of the surface water was brought forward. The keystone of the way and the detailed arithmetic of the network training were given. The example shows that the model has highly forecasting precision. 展开更多
关键词 相空间重建 神经网络 资源量 地表水 预测模型
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Evaluation of Animal and Plant Resources Status Quo after the Reservoir Construction in Turks River and Protection Measures 被引量:2
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作者 Tuerxunayi.Aibibulla Nuerbayi.Abudoushalike Adilijiang.Kuerban 《Meteorological and Environmental Research》 CAS 2011年第6期96-98,共3页
[Objective] The aim was to assess the status quo of animal and plant resources in Turks River after the construction of the reservoir.[Method] Through field investigation,document check and sample identification,the d... [Objective] The aim was to assess the status quo of animal and plant resources in Turks River after the construction of the reservoir.[Method] Through field investigation,document check and sample identification,the distribution of animal and plants resources in Turks River after the construction of the reservoir was studied and corresponding protection measures were proposed.[Result] Under the influence of reservoir,there were fifteen types of rare animals,one species of national primary protected animals,seven species of national secondary protected animals,one species of provincial primary protected animals,six species of provincial secondary protected animals;there were twenty one species of rare plants,including two species of national secondary plant,five species of national tertiary protected animals,six types of Xinjiang primary protected plants,two species of Xinjiang secondary protected plants and six types of tertiary protected plants in Xinjiang.Protective policies for the land ecological environment were proposed,including corresponding compensation according to the rules and policies of government,plans being formulated for rare species protection,construction of natural reserves and artificial breeding base,usage of the environment in the reservoir and changes of ecological situation etc.[Conclusion] The study provided basis for the protection of animal and plants resources in Turks. 展开更多
关键词 TURKS RIVER RESERVOIR construction ANIMAL and PLANT RESOURCES China
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Long Term Effects of Farming System on Soil Water Content and Dry Soil Layer in Deep Loess Profile of Loess Tableland in China 被引量:11
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作者 CHENG Li-ping LIU Wen-zhao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第6期1382-1392,共11页
Soil water is strongly affected by land use/cover in the Loess Plateau in China. Water stored in thick loessal soils is one of the most important resources regulating vegetation growth. However, soil water in the deep... Soil water is strongly affected by land use/cover in the Loess Plateau in China. Water stored in thick loessal soils is one of the most important resources regulating vegetation growth. However, soil water in the deep loess profile, which is critical for maintaining the function of the "soil water pool" is rarely studied because deep profile soil samples are difficult to collect. In this study, four experimental plots were established in 2005 to represent different farming systems on the Changwu Tableland: fallow land, fertilized cropland, unfertilized cropland, and continuous alfalfa. The soil water content in the 15-m-deep loess profiles was monitored continuously from 2007 to 2012 with the neutron probe technique. The results showed that temporal variations in soil water profiles differed among the four farming systems. Under fallow land, the soil water content increased gradually over time, first in the surface layers and later in the deep soil layers. In contrast, the soil water content decreased gradually under continuous alfalfa. The distributions of soil water in deep soil layers under both fertilized and unfertilized cropland were relatively stable over time. Thus farming system significantly affected soil water content. Seven years after the start of the experiment, the soil water contents in the 15-m-deep profiles averaged 23.4% under fallow land, 20.3% under fertilized cropland, 21.6% under unfertilized cropland, and 16.0% under continuous alfalfa. Compared to measurements at the start of the experiment, both fallow land and unfertilized cropland increased soil water storage in the 15-m loess profiles. In contrast, continuous alfalfa reduced soil water storage. Fertilized cropland has no significant effect on soil water storage. These results suggest that deep soil water can be replenished under the fallow and unfertilized farming systems. Dry soil layers(i.e., those which have soil water content less than the stable field water capacity) in the subsoil of the Changwu Tableland region can be classified as either temporary dry soil layers or persistent dry soil layers. Temporary dry soil layers, which typically form under annual crops, often disappear during wet years. Persistent dry soil layers generally develop under perennial vegetation. Even after removing the vegetation, persistent dry soil layers remain for several decades. This study provides information useful for the conservation and utilization of soil water resources in the Loess Tableland. 展开更多
关键词 土壤含水量 土壤干层 耕作制度 黄土塬 中国 土壤水分含量 土地利用 覆盖 农田施肥
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Effects of grazing on net primary productivity,evapotranspiration and water use efficiency in the grasslands of Xinjiang,China 被引量:9
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作者 HUANG Xiaotao LUO Geping +1 位作者 YE Feipeng HAN Qifei 《Journal of Arid Land》 SCIE CSCD 2018年第4期588-600,共13页
Grazing is a main human activity in the grasslands of Xinjiang, China. It is vital to identify the effects of grazing on the sustainable utilization of local grasslands. However, the effects of grazing on net primary ... Grazing is a main human activity in the grasslands of Xinjiang, China. It is vital to identify the effects of grazing on the sustainable utilization of local grasslands. However, the effects of grazing on net primary productivity(NPP), evapotranspiration(ET) and water use efficiency(WUE) in this region remain unclear. Using the spatial Biome-BGC grazing model, we explored the effects of grazing on NPP, ET and WUE across the different regions and grassland types in Xinjiang during 1979–2012. NPP, ET and WUE under the grazed scenario were generally lower than those under the ungrazed scenario, and the differences showed increasing trends over time. The decreases in NPP, ET and WUE varied significantly among the regions and grassland types. NPP decreased as follows: among the regions, Northern Xinjiang(16.60 g C/(m^2·a)), Tianshan Mountains(15.94 g C/(m^2·a)) and Southern Xinjiang(-3.54 g C/(m^2·a)); and among the grassland types, typical grasslands(25.70 g C/(m^2·a)), swamp meadows(25.26 g C/(m^2·a)), mid-mountain meadows(23.39 g C/(m^2·a)), alpine meadows(6.33 g C/(m^2·a)), desert grasslands(5.82 g C/(m^2·a)) and saline meadows(2.90 g C/(m^2·a)). ET decreased as follows: among the regions, Tianshan Mountains(28.95 mm/a), Northern Xinjiang(8.11 mm/a) and Southern Xinjiang(7.57 mm/a); and among the grassland types, mid-mountain meadows(29.30 mm/a), swamp meadows(25.07 mm/a), typical grasslands(24.56 mm/a), alpine meadows(20.69 mm/a), desert grasslands(11.06 mm/a) and saline meadows(3.44 mm/a). WUE decreased as follows: among the regions, Northern Xinjiang(0.053 g C/kg H_2O), Tianshan Mountains(0.034 g C/kg H_2O) and Southern Xinjiang(0.012 g C/kg H_2O); and among the grassland types, typical grasslands(0.0609 g C/kg H_2O), swamp meadows(0.0548 g C/kg H_2O), mid-mountain meadows(0.0501 g C/kg H_2O), desert grasslands(0.0172 g C/kg H_2O), alpine meadows(0.0121 g C/kg H_2O) and saline meadows(0.0067 g C/kg H_2O). In general, the decreases in NPP and WUE were more significant in the regions with relatively high levels of vegetation growth because of the high grazing intensity in these regions. The decreases in ET were significant in mountainous areas due to the terrain and high grazing intensity. 展开更多
关键词 土壤水分蒸发蒸腾损失总量 草地类型 生产率 擦伤 中国 H2O NPP WUE
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Structural Characterization and Retention Time Prediction for Components of Essential Oil of Meconopsis Integrifolia Flowers 被引量:5
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作者 廖立敏 李建凤 +1 位作者 卿东红 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第11期1638-1645,共8页
A molecular structural characterization (MSC) method called reduced molecular electronegativity-distance vector (MEDVR) was used to describe the molecular structures of 55 components of meconopsis integrifolia flowers... A molecular structural characterization (MSC) method called reduced molecular electronegativity-distance vector (MEDVR) was used to describe the molecular structures of 55 components of meconopsis integrifolia flowers. By use of stepwise multiple regression (SMR) and partial least square (PLS) methods, a model with the correlation coefficient (R1) of 0.987 and the standard deviation (SD1) of 1.377 could be obtained. Then through multiple linear regression (MLR), another model with the correlation coefficient (R2) of 0.989 and standard deviation (SD2) of 1.395 could be constructed. Furthermore, in virtue of variable screening by the stepwise multiple regression technique (SMR), 8 vectors were selected to build up another model with its correlation coefficient (R3) and standard deviation (SD3) of 0.989 and 1.366, respectively. Then all the three models were evaluated by performing cross-validation with the leave-one-out (LOO) procedure, and the correlation coefficients (QCV) were 0.981, 0.976 and 0.979, respectively. The results show that the models constructed could provide estimation stability and favorable predictive ability. 展开更多
关键词 挥发油成分 绿绒蒿 时间预测 结构表征 分子电性距离矢量 相关系数 多元逐步回归 多元线性回归
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Identifying the influence of urbanization on soil organic matter content and p H from soil magnetic characteristics 被引量:4
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作者 YANG Han XIONG Heigang +2 位作者 CHEN Xuegang WANG Yaqi ZHANG Fang 《Journal of Arid Land》 SCIE CSCD 2015年第6期820-830,共11页
Soil magnetic characteristics are correlated with soil p H and organic matter content. Analyzing soil magnetic characteristics, organic matter content and p H can indirectly evaluate soil pollution caused by human act... Soil magnetic characteristics are correlated with soil p H and organic matter content. Analyzing soil magnetic characteristics, organic matter content and p H can indirectly evaluate soil pollution caused by human activities. This study analyzed the soil magnetic characteristics, organic matter content and p H in surface soil samples from different land use types in Shihezi city, a newly and rapidly developing oasis city in Xinjiang of China. The aims of this study were to explore the possible relationships among the soil magnetic parameters and thereby improve the understanding of influence of urbanization on soil properties. Eighty surface soil samples at the depth of 0–10 cm were collected from 29 July to 4 August 2013. The results showed that the magnetic minerals in surface soil were dominated by ferromagnetic minerals. Spatially, the magnetic susceptibility(χLF), anhysteretic remanent magnetization susceptibility(χARM), saturation isothermal remanent magnetization(SIRM) and "soft" isothermal remanent magnetization(SOFT) were found to be most dominant in the new northern urban area B(N-B), followed by built-up areas(U), suburban agricultural land(F), and then the new northern urban area A(N-A). The values of χLF, χARM, SIRM and SOFT were higher in the areas with high intensities of human activities and around the main roads. Meanwhile, the property "hard" isothermal remanent magnetization(HIRM) followed the order of U>N-B>F>N-A. Built-up areas had an average p H value of 7.93, which was much higher than that in the new northern urban areas as well as in suburban agricultural land, due to the increased urban pollutant emissions. The average value of soil organic matter content in the whole study area was 34.69 g/kg, and the values in the new northern urban areas were much higher than those in the suburban agricultural land and built-up areas. For suburban agricultural land, soil organic matter content was significantly negatively correlated with χLF, and had no correlation with other magnetic parameters, since the soil was frequently ploughed. In the new northern urban areas(N-A and N-B), there were significant positive correlations of soil organic matter contents with χARM, SIRM, SOFT and HIRM, because natural grasslands were not frequently turned over. For the built-up areas, soil organic matter contents were significantly positively correlated with χLF, χARM, SIRM and SOFT, but not significantly correlated with frequency-dependent susceptibility(χFD, expressed as a percentage) and HIRM, because the soil was not frequently turned over or influenced by human activities. The results showed that soil magnetic characteristics are related to the soil turnover time. 展开更多
关键词 土壤有机质含量 土壤磷含量 饱和等温剩磁 人类活动影响 非磁滞剩磁 铁磁性矿物 正相关关系 磁性特征
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Accumulation of Rare Earth Elements in Spinach and Soil under Condition of Using REE and Acid Rain Stress 被引量:4
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作者 严重玲 洪业汤 +3 位作者 林鹏 王世杰 李心清 梁洁 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第2期132-138,共7页
The content and distribution characteristics of REE in spinach and soil under using REE and acid rain stress were studied by pot experiments. The results show that the content of REE is 0 527~0 696 (μg·g -1 ) i... The content and distribution characteristics of REE in spinach and soil under using REE and acid rain stress were studied by pot experiments. The results show that the content of REE is 0 527~0 696 (μg·g -1 ) in the above ground portion of spinach, 2 668~3 003 (μg·g -1 ) in the under ground portion of spinach and 229 09~250 30 (μg·g -1 ) in the soil. With the acidity of acid rain increasing, the leaching of REE in plants and soil is strengthened and the amount of REE reduces with decreasing of pH value. After REE are used, though plants show the selective absorption to Ce group elements (especially spraying on leaves), regardless under acid rain stress or using REE or not, the distribution model of REE in the above ground and under ground portion of plants is basically the same with the control. Plants also follow the Oddo Harkins rule of the REE of distribution abundance, light rare earth elements is enriched, the minus of Eu is abnormal and admeasure of Ce is a rich model. The results show that REE in plants mainly come from soil and are affected by it. 展开更多
关键词 菠菜 土壤 稀土 酸雨 积聚 pH值 REE
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Compositional and Structural Difference of Fulvic Acid from Black Soil Applied with Different Organic Materials: Assessment After Three Years 被引量:3
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作者 LI Jian-ming WU Jing-gui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第10期1865-1871,共7页
Knowledge of different effects of various organic materials on soil humic substance is important for both environmental safety and sustainable agriculture.A pot experiment was conducted at Jilin Agricultural Universit... Knowledge of different effects of various organic materials on soil humic substance is important for both environmental safety and sustainable agriculture.A pot experiment was conducted at Jilin Agricultural University,Jilin Province in northeast China to discover the influence of herb residue,animal excrement,woody residue,animal remnant on fulvic acid(FA) composition and structure using differential thermal analysis-thermogravimetric(DTA-TG),fourier transform infrared spectroscopy(FTIR) and elemental analysis.DTA-TG showed the range of peak temperature in the first exothermic reaction increased following the trend: CK>herb residue>animal excrement>woody residue=animal remnant,and the most weight loss was observed in animal excrement.Moreover,the second exothermic reaction of CK-and animal excrement-FA was presented as double peaks,the order of weight loss in that area was animal remnant>CK>woody residue>animal excrement>herb residue.According to FTIR,herb residue displayed higher adsorption intensity at 2 950,1 420,1 240 and 1 030 cm-1,animal excrement was in reverse.At the same time,herb residue-and animal excrement-FA had an absorption peak at 1 720 cm-1,while other organic materials didn't have this peak.As elemental analysis showed,FA isolated from various treatments was significantly distinct.It was clearly shown from our results that FA composition and structure in amended soils may be affected in different ways and at various extents on dependence of the nature and origin of amendment. 展开更多
关键词 黄腐酸 结构 物料成分 傅立叶变换红外光谱 动物排泄物 DTA-TG 应用 黑土
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Characterizing urban expansion of Korla City and its spatial-temporal patterns using remote sensing and GIS methods 被引量:5
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作者 Bumairiyemu MAIMAITI DING Jianli +1 位作者 Zibibula SIMAYI Alimujiang KASIMU 《Journal of Arid Land》 SCIE CSCD 2017年第3期458-470,共13页
Cities provide spatial contexts for populations and economic activities. Determining the spatial-temporal patterns of urban expansion is of particular significance for regional sustainable development. To achieve a be... Cities provide spatial contexts for populations and economic activities. Determining the spatial-temporal patterns of urban expansion is of particular significance for regional sustainable development. To achieve a better understanding of the spatial-temporal patterns of urban expansion of Korla City, we explore the urban expansion characteristics of Korla City over the period 1995–2015 by employing Landsat TM/ETM+ images of 1995, 2000, 2005, 2010, and 2015. Urban land use types were classified using the supervised classification method in ENVI 4.5. Urban expansion indices, such as expansion area, expansion proportion, expansion speed, expansion intensity, compactness, and fractal dimension, were calculated. The spatial-temporal patterns and evolution process of the urban expansion(e.g., urban gravity center and its direction of movement) were then quantitatively analyzed. The results indicated that, over the past 25 years, the area and proportion of urban land increased substantially with an average annual growth rate of 15.18%. Farmland and unused land were lost greatly due to the urban expansion. This result might be attributable to the rapid population growth and the dramatic economic development in this area. The city extended to the southeast, and the urban gravity center shifted to the southeast as well by about 2118 m. The degree of urban compactness tended to decrease and the fractal dimension index tended to increase, indicating that the spatial pattern of Korla City was becoming loose, complex, and unstable. This study could provide a scientific reference for the studies on urban expansion of oasis cities in arid land. 展开更多
关键词 城市的扩大 空间时间的变化 城市的土地 遥感和 GIS Korla 城市
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Development and Characterization of Microsatellite Markers in Brassica rapa ssp.chinensis and Transferability Among Related Species 被引量:4
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作者 CUI Xiu-min DONG Yu-xiu +3 位作者 HOU Xi-lin CHENG-Yan ZHANG Jing-yi JIN Min-feng 《Agricultural Sciences in China》 CAS CSCD 2008年第1期19-31,共13页
Simple sequence repeat (SSR) or microsatellite marker is a valuable tool for several purposes,such as mapping,fingerprinting,and breeding. In the present study,an inter-simple sequence repeat (ISSR)-PCR technique was ... Simple sequence repeat (SSR) or microsatellite marker is a valuable tool for several purposes,such as mapping,fingerprinting,and breeding. In the present study,an inter-simple sequence repeat (ISSR)-PCR technique was applied for developing SSR markers in non-heading Chinese cabbage (Brassica rapa). A total of 190 SSRs were obtained. Among these,AG or CT (54.7%) was the most frequent repeat,followed by AC or GT (31.6%) of the microsatellites. The average number of the SSRs length array was 16 and 10 times,respectively. Based on the determined SSR sequences,143 SSR primer pairs were designed to evaluate their transferabilities among the related species of Brassica. The number of alleles produced per marker averaged 2.91,and the polymorphism information content (PIC) value ranged from 0 to 0.863 with an average of 0.540. Monomorphism was observed in 16 primer pairs. The transferability percentage in CC genome was higher than in BB genome. More loci occurred in the BBCC genome. This result supported the hypothesis that BB genome was divergent from A and C genomes,and AA and CC genomes were relatively close. The polymorphic primers can be exploited for further evolution,fingerprinting,and variety identification. 展开更多
关键词 芸苔 微卫星标记 遗传多态性 可转移性
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Effect of the W-beam central guardrails on wind-blown sand deposition on desert expressways in sandy regions 被引量:2
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作者 WANG Cui LI Shengyu +2 位作者 LEI Jiaqiang LI Zhinong CHEN Jie 《Journal of Arid Land》 SCIE CSCD 2020年第1期154-165,共12页
Many desert expressways are affected by the deposition of the wind-blown sand,which might block the movement of vehicles or cause accidents.W-beam central guardrails,which are used to improve the safety of desert expr... Many desert expressways are affected by the deposition of the wind-blown sand,which might block the movement of vehicles or cause accidents.W-beam central guardrails,which are used to improve the safety of desert expressways,are thought to influence the deposition of the wind-blown sand,but this has yet not to be studied adequately.To address this issue,we conducted a wind tunnel test to simulate and explore how the W-beam central guardrails affect the airflow,the wind-blown sand flux and the deposition of the wind-blown sand on desert expressways in sandy regions.The subgrade model is 3.5 cm high and 80.0 cm wide,with a bank slope ratio of 1:3.The W-beam central guardrails model is 3.7 cm high,which included a 1.4-cm-high W-beam and a 2.3-cm-high stand column.The wind velocity was measured by using pitot-static tubes placed at nine different heights(1,2,3,5,7,10,15,30 and 50 cm)above the floor of the chamber.The vertical distribution of the wind-blown sand flux in the wind tunnel was measured by using the sand sampler,which was sectioned into 20 intervals.In addition,we measured the wind-blown sand flux in the field at K50 of the Bachu-Shache desert expressway in the Taklimakan Desert on 11 May 2016,by using a customized 78-cm-high gradient sand sampler for the sand flux structure test.Obstruction by the subgrade leads to the formation of two weak wind zones located at the foot of the windward slope and at the leeward slope of the subgrade,and the wind velocity on the leeward side weakens significantly.The W-beam central guardrails decrease the leeward wind velocity,whereas the velocity increases through the bottom gaps and over the top of the W-beam central guardrails.The vertical distribution of the wind-blown sand flux measured by wind tunnel follows neither a power-law nor an exponential function when affected by either the subgrade or the W-beam central guardrails.At 0.0H and 0.5H(where H=3.5 cm,which is the height of the subgrade),the sand transport is less at the 3 cm height from the subgrade surface than at the 1 and 5 cm heights as a result of obstruction by the W-beam central guardrails,and the maximum sand transportation occurs at the 5 cm height affected by the subgrade surface.The average saltation height in the presence of the W-beam central guardrails is greater than the subgrade height.The field test shows that the sand deposits on the overtaking lane leeward of the W-beam central guardrails and that the thickness of the deposited sand is determined by the difference in the sand mass transported between the inlet and outlet points,which is consistent with the position of the minimum wind velocity in the wind tunnel test.The results of this study could help us to understand the hazards of the wind-blown sand onto subgrade with the W-beam central guardrails. 展开更多
关键词 wind velocity field wind-blown sand flux W-beam central guardrails sand deposition desert expressway wind tunnel test Taklimakan Desert
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Influence of tourist disturbance on soil properties, plant communities, and surface water quality in the Tianchi scenic area of Xinjiang, China 被引量:2
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作者 WEN Bin ZHANG Xiaolei +2 位作者 YANG Zhaoping XIONG Heigang QIU Yang 《Journal of Arid Land》 SCIE CSCD 2016年第2期304-313,共10页
The impact of tourist disturbance on the environment has become a focal issue of environmental science, ecology, and travel management studies. To assess the influence of tourist disturbance on soils and plants in the... The impact of tourist disturbance on the environment has become a focal issue of environmental science, ecology, and travel management studies. To assess the influence of tourist disturbance on soils and plants in the Tianchi scenic area of Xinjiang, China, we compared soil properties and plant community characteristics at 0, 5, 10, and 20 m from the tourist trail within areas at three different altitudes, where the intensities of tourist disturbance are distinct. Surface water quality was also studied at three different levels relative to the Tianchi Lake. The results showed that tourist disturbance significantly increased soil p H within 10 m from the trail and soil bulk density on the edge of the trail, but significantly reduced soil organic matter and total nitrogen contents within 5 m from the trail. The number of tree seedlings on the edge of the trail and the shrub coverage and height of herbaceous plants within 5 m from the trail significantly decreased due to tourist disturbance. Changes in herbaceous plant diversity differed by soil zones. In the high altitude region, tourist disturbance led to a remarkable increase in the herbaceous plant diversity on the edge of the trail, while in the low altitude region, tourist disturbance had a low impact on the diversity of herbaceous plants. In addition, tourist activities polluted the surface water, significantly reducing water quality. Thus, current tourist activities have a significant negative impact on the ecological environment in the Tianchi scenic area. 展开更多
关键词 植物群落特征 旅游干扰 土壤性质 风景区 地表水 天池 水质 新疆
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Study on the Effect of Indolebutyric Acid-Lanthanum Chelate on Vegetable Growth and Its Molecular Mechanism
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作者 Chenxia Wang Yan Li +2 位作者 Qing Chen Jianyu Cui Kangguo 《Journal of Agricultural Science and Technology(B)》 2020年第5期286-297,共12页
In order to reduce the non-point source pollution caused by the large or excessive application of chemical fertilizers and pesticides,this study was aimed to develop new alternative functional substances.The effects o... In order to reduce the non-point source pollution caused by the large or excessive application of chemical fertilizers and pesticides,this study was aimed to develop new alternative functional substances.The effects of different concentrations of indolebutyric acid-lanthanum chelate on seed germination and tomato seedling growth were studied by germination test of cucumber and tomato seeds and pot experiment of tomato seedlings.The results showed that the optimum concentration of indolebutyric acid-lanthanum chelate could promote the germination and growth of tomato and cucumber seeds.Among them,0.02 mg/L of indolebutyric acid-lanthanum chelate is the optimum concentration for tomato and cucumber seed germination.When the concentration is 0.1 mg/L,it is the optimum concentration for radicle and hypocotyl growth.In the pot experiment,when the optimum concentration of indolebutyric acid-lanthanum chelate on tomato seedlings was 0.5 mg/L,the plant height,stem diameter,aboveground biomass,underground biomass and leaf area of tomato seedlings could be significantly promoted.At the same time,the absorption of the main elements P,K,Mg and trace elements Fe,Mn,Cu,Zn and Na and their transfer from the underground part to the aboveground part of the seedlings were enhanced.The relative expression of the tomato expansion protein genes leEXP2,leEXP18 and leEXP5 was also significantly increased.Therefore,the suitable concentration of indolebutyric acid-lanthanum chelate has the effect of promoting root growth and promoting the quality of tomato seedlings. 展开更多
关键词 Indolebutyric acid-lanthanum chelate promote root growth fertilizer reduction CUCUMBER tomato
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Particle Size and Shape of On-road Suspended Coarse Dust in the Shijiazhuang City, China
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作者 Z.H. Wang Z.P. Hao 《Journal of Environmental Science and Engineering》 2011年第1期21-27,共7页
关键词 形状参数 悬浮微粒 颗粒大小 道路环境 石家庄市 中国 空气动力学 粒子大小
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Coarse aerosol particle size and shape characteristics near ground level of Shijiazhuang city, China
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作者 WANG Zan-hong ZHANG Yu-liang +4 位作者 ZHAO Zhou ZHANG Su-min ZHANG Wen-zong WANG Yun-xiu WEI Li -tao 《Journal of Environmental Science and Engineering》 2007年第1期48-54,共7页
关键词 气溶胶粒子 颗粒形状 石家庄市 粒径分布 地面水 特征和 非采暖期 中国
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QSRR Study on the Components of Styrax Japonicus Sieb Flowers Using Improved Molecular Electronegativity-distance Vector (I-MEDV) 被引量:9
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作者 廖立敏 朱俊 +1 位作者 李建凤 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第1期105-110,共6页
Atoms in most organic molecules are often carbon,oxygen,nitrogen,sulfur,halogens,etc. Based on the three-dimensional structure of a molecule,a molecular structural characterization(MSC) method called improved molecula... Atoms in most organic molecules are often carbon,oxygen,nitrogen,sulfur,halogens,etc. Based on the three-dimensional structure of a molecule,a molecular structural characterization(MSC) method called improved molecular electronegativity-distance vector(I-MEDV) was developed. It was used to describe the structures of 37 compounds of styrax japonicus sieb flowers. Through multiple linear regression(MLR),a QSRR model was built up. The correlation coefficient(R1) of the model was 0.980. Then,4 vectors were selected to build another model through the method of stepwise multiple regression(SMR) ,and the correlation coefficient(R2) of the model was 0.975. Moreover,all the two models were evaluated by performing the crossvalidation with the leave-one-out(LOO) procedure and the correlation coefficients(Rcv) were 0.948 and 0.968,respectively. The results show that the I-MEDV could successfully describe the structures of organic compounds. The stability and predictability of the models were good. 展开更多
关键词 分子电性距离矢量 MEDV QSRR 茉莉 刺参 分子三维结构 有机化合物 组件
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Low-carbon economic development in Central Asia based on LMDI decomposition and comparative decoupling analyses 被引量:4
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作者 LI Jiaxiu CHEN Yaning +1 位作者 LI Zhi HUANG Xiaotao 《Journal of Arid Land》 SCIE CSCD 2019年第4期513-524,共12页
Low-carbon economic development is a strategy that is emerging in response to global climate change. Being the third-largest energy base in the world, Central Asia should adopt rational and efficient energy utilizatio... Low-carbon economic development is a strategy that is emerging in response to global climate change. Being the third-largest energy base in the world, Central Asia should adopt rational and efficient energy utilization to achieve the sustainable economic development. In this study, the logarithmic mean Divisia index(LMDI) decomposition method was used to explore the influence factors of CO2 emissions in Central Asia(including Kazakhstan, Uzbekistan, Kyrgyzstan, Tajikistan and Turkmenistan) during the period 1992–2014. Moreover, decoupling elasticity and decoupling index based on the LMDI decomposition results were employed to explore the relationship between economic growth and CO2 emissions during the study period. Our results show that the total CO2 emissions decreased during the period 1992–1998, influenced by the collapse of the Soviet Union in 1991 and the subsequent financial crisis. After 1998, the total CO2 emissions started to increase slowly along with the economic growth after the market economic reform. Energy-related CO2 emissions increased in Central Asia, mainly driven by economic activity effect and population effect, while energy intensity effect and energy carbon structure effect were the primary factors inhibiting CO2 emissions. The contribution percentages of these four factors(economic activity effect, population effect, energy intensity effect and energy carbon structure effect) to the total CO2 emissions were 11.80%, 39.08%, –44.82% and –4.32%, respectively, during the study period. Kazakhstan, Uzbekistan and Turkmenistan released great quantities of CO2 with the annual average emissions of 189.69×106, 45.55×106 and 115.38×106 t, respectively. In fact, their economic developments depended on high-carbon energies. The decoupling indices clarified the relationship between CO2 emissions and economic growth, highlighting the occurrence of a ’’weak decoupling’’ between these two variables in Central Asia. In conclusion, our results indicate that CO2 emissions are still not completely decoupled from economic growth in Central Asia. Based on these results, we suggest four key policy suggestions in this paper to help Central Asia to reduce CO2 emissions and build a resource-conserving and environment-friendly society. 展开更多
关键词 energy-related CO2 emissions low-carbon ECONOMY LMDI DECOMPOSITION DECOUPLING ELASTICITY DECOUPLING index Central Asia
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Morphology of single inhalable particle in the air polluted city of Shijiazhuang,China 被引量:1
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作者 WANG Zanhong ZHANG Lingzhi +2 位作者 ZHANG Yuliang ZHAO Zhou ZHANG Sumin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第4期429-435,共7页
在典型的空中, Shijiazhuang,在非加热的时期的单个 inhalable 粒子样品,加热时期,灰尘暴风雨天,和雪的天的弄脏的城市被 SEM/EDS 收集并且检测(扫描电子显微镜学和精力散 X 光检查光谱测定) 。粒子形态学被 6 形状簇描绘,它是:... 在典型的空中, Shijiazhuang,在非加热的时期的单个 inhalable 粒子样品,加热时期,灰尘暴风雨天,和雪的天的弄脏的城市被 SEM/EDS 收集并且检测(扫描电子显微镜学和精力散 X 光检查光谱测定) 。粒子形态学被 6 形状簇描绘,它是:不规则的平方,聚结成块的,范围,絮状物,列或棍子,并且未知,由量的顺序。不规则的方形的粒子在各种样品是普通的;范围粒子是更多,并且列或棍子是在冬季样品的更少;在湿存款样品,聚结,絮状物粒子没被发现。大多数粒子的表面与分数维的边是粗糙的,它能在弄脏的大气的环境提供合适的化学反应床。新形成的钙水晶被发现表明抵销的反应的存在,解释为在 Shijiazhuang 的高 SO2 排放和低酸雨频率的原因。范围的三种表面模式光滑、半光滑、粗糙,相应于元素 Si 主导, Si-Al-dominant,并且 Fe 主导。煤烟粒子在 10 μ m 附近与平均尺寸表现为絮状物,比前者更加大报导了结果,但是包或与另外的好粒子捕获了使它的外观唯一并且潜在地提高它的毒性。新形成的钙水晶, 3 种范围表面模式,和唯一的煤烟外观在 Shijiazhuang 城市里代表单个 inhalable 粒子的形态学特征。 展开更多
关键词 形态学 钙离子 晶体 烟灰
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Projections of temperature extremes based on preferred CMIP5 models:a case study in the Kaidu-Kongqi River basin in Northwest China
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作者 CHEN Li XU Changchun LI Xiaofei 《Journal of Arid Land》 SCIE CSCD 2021年第6期568-580,共13页
The extreme temperature has more outstanding impact on ecology and water resources in arid regions than the average temperature.Using the downscaled daily temperature data from 21 Coupled Model Inter-comparison Projec... The extreme temperature has more outstanding impact on ecology and water resources in arid regions than the average temperature.Using the downscaled daily temperature data from 21 Coupled Model Inter-comparison Project(CMIP)models of NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP)and the observation data,this paper analyzed the changes in temporal and spatiotemporal variation of temperature extremes,i.e.,the maximum temperature(Tmax)and minimum temperature(Tmin),in the Kaidu-Kongqi River basin in Northwest China over the period 2020–2050 based on the evaluation of preferred Multi-Model Ensemble(MME).Results showed that the Partial Least Square ensemble mean participated by Preferred Models(PM-PLS)was better representing the temporal change and spatial distribution of temperature extremes during 1961–2005 and was chosen to project the future change.In 2020–2050,the increasing rate of Tmax(Tmin)under RCP(Representative Concentration Pathway)8.5 will be 2.0(1.6)times that under RCP4.5,and that of Tmin will be larger than that of Tmax under each corresponding RCP.Tmin will keep contributing more to global warming than Tmax.The spatial distribution characteristics of Tmax and Tmin under the two RCPs will overall the same;but compared to the baseline period(1986–2005),the increments of Tmax and Tmin in plain area will be larger than those in mountainous area.With the emission concentration increased,however,the response of Tmax in mountainous area will be more sensitive than that in plain area,and that of Tmin will be equivalently sensitive in mountainous area and plain area.The impacts induced by Tmin will be universal and farreaching.Results of spatiotemporal variation of temperature extremes indicate that large increases in the magnitude of warming in the basin may occur in the future.The projections can provide the scientific basis for water and land plan management and disaster prevention and mitigation in the inland river basin. 展开更多
关键词 temperature extremes multi-model ensemble RCP PROJECTION Kaidu-Kongqi River basin
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